To achieve scaling down and high integration of pattern generating apparatuses, a lithography technology using Extreme Ultra Violet (EUV) light source has been developed. In the lithography using the EUV light source, a wavelength of the light source is shorter than that of an argon fluoride (ArF) light source. Thus this exposure apparatus generates large scattering in a reduction optical system. The scattered light (flare) may cause light leakage from an opening portion of a mask pattern, thus varying a size of a resist pattern formed on a substrate. In order to reduce an influence of the flare and evaluate an optical proximity effect precisely, a dummy pattern may be disposed around a pattern to be evaluated so as to ensure uniform flare intensity.